Electric switch



March 30,;1926. 1,578,485

j s. H. TODD ELECTRIC SWITCH Filed May 6, 1922 the bridging memberPatented Mar. 30, 1926.

-UNITED STATES SAMUEL H. TODD, OF HIGHLAND PARK, MICHIGAN.

ELECTRIC swr'ro -I.

I Application filed May 6, 1922. Serial No. 558,854.

To all whom it may concerm Be it known that SAMUEL H. Toon, a citizen ofthe United States, residing at Highland Park, in the county of Wayne andState of Michigan, has invented certain new and useful Improvements inElectric Switches, of which the following is a specification.

This invention relates to electric switches and especiallyv to anelectric switch which can be operated by a thermostat. It is the objectof the invention to provide a switch which can be operated by a smallamount of movement and which when moved a small initial distance willcomplete the movement by ener y stored duringthe initial movement. Byusing this stored energy a quick snappy final movement of the switch ishad.

Another feature of this switch is that on the breaking of theconnections the initialmovement of the switch arts does not lift uringthe initial movement, but'only, when the parts have reached the pointwhere the stored energy is drawn upon, is the switch broken. This,therefore, permits the switch to snap open with a thermostat as anactuator which obviously moves very slow. A slow opening or closing ofthe switch results in objectionable arcing of the current.

The switch is simple in construction, cheap to manufiicture 3 andeffective in giving a snappingaction, both in opening and closing theswitch member. This will be described more in detail in the drawingsfollowlng.

In the drawings:

Fig. 1 is a plan view of the switch.

Fig. 2 is a vertical section on the line 2-2 of Fig. 1.

Fig. 3 is a section on the line 33 of 'Fig.v

Fig. 4 is' a section on the-line 44 of Fig.

a designates a housing made of bakelite, hard rubber or other insulatingmaterial. This is provided with a cap or lid 6. A pair of terminals 0and d run through the housing. In the center of the housing is a pair ofupstanding lugs on which is secured by screws a standard a. Thisstandard is in the form of a yoke or an inverted U. In each side of theleg of the yoke is a deep groove f, adapted to take the knife edge ofthe U-arms g and 70. Each U--arm is prothe U-arm against lateralmovement.

vided with a pair of extensions y that fit to the inside of thestandards so as to hold A tractile spring 71. is fastened to theconnecting bar portion of each U-arm. The upward movement of the 'U-armsconnected by the spring is limited by the two contacts a and (Z. Thedownward movement by the shoulder j-and the housing.

One of these U-arms constitutes an elec tric bridge from contact tocontact, namely the arm is. The other U-arin g has no electricfunctions, but it does play an important part in doing the initiatorywork of the switch in storing energy or permitting the active orbridging arm to rest until energy suflicient for a quick snappy breakingor closing action is provided. This is a very important factor in switchoperation as it eliminates arcing, due to a slow closure such asnormally procured by the movement of a thermostat.

This snappy action is procured by the araction permitted by putting aspring under strain, but there is this distinguishing feature, that thearms are tied together by only a tractile spring so that in initiatingthe movement in either direction only the arm 9 is moved until astraight line position is achieved and crossed, whereupon the springacts upon the other bridge arm to snap it open or closed.

The arm 9 is provided with laterally projecting lugs m which engagethrough a slot in the levers 'n pivoted to the uprights of the standard.The end of one of these levers bent around to form 2. lug 0 which passesthough the slot 10 in the slide 9. This slide is in the form of a yokeas appears by Fig. 3 so as to provide actuation for levers n on bothsides of the arm. A draw bar 1' is fastened to the bottom of the yokeand passes through the opening 8 in the bottom of the switch housing.This may be connected with a line position will simply draw the. switcharm 1; against the shoulder j until the straight line position of thetwo arms is crossed. At this point the spring h is put under itsgreatest tension and has considerable energy stored, hence immediatelythe straight line position is crossed it snaps the switch arm rupagainst the contacts c with a quick snappy action that avoids arcing.What I claim is: 4

1. In an electric switch, the combination ofa standard, a .pair of armspivoted to swing on opposite sides of the standard, a spring between thetwo arms for resisting movement of the arms from one side to the otherof a straight line position, a pair of contacts engaged by one arm, anda yoke-like slide 'slidably secured on the standard and a pair of leversconnecting the yokerlike member with the other arm to actuate the same v2. In an electric switch; the combination apair of contacts engagedbyone swin' ing arm, a yoke member having each arm slidably secured to thestandard, and a pair of said yoke member and at the other end to theother swinging arm to actuate the same.

3. In an electric switch, the combination of a standard, a pair of armspivoted. to swing on opposite sides of the standard, a spring betweenthe two swinging arms for resisting the movement of the arms from oneside to the other of a straight line position, a member slidably securedto the standard and having a relatively small movement, a lever securedat one end to the slidable memher and at the other end to one swingingarm to impart a greater relative movement to said swinging arm thanwould be possible by direct connection ofv said slidable member-withsaid swinging arm.

In testimony whereof I aflix my signature.

' SAMUEL H. TODD.

of links each secured at one end to an arm I

